The director of Vexed has praised the show's stars.

The series focuses on a pair of police detectives played by Toby Stephens and Lucy Punch.

Writing on the BBC Comedy Blog, director Matt Lipsey explained that it is difficult to cast characters who are "dysfunctional, neurotic, sexist, quarrelsome, self-righteous and paranoid".

"Couple these elements with a need for them to be sexy, bright and warm people you genuinely want to spend time around," he continued. "As you can see, this was going to be more than a little tricky to cast."

However, Lipsey described Stephens as a "really refreshing and surprising" choice for the show's character Jack, adding: "He manages to imbue Jack with a likeability by allowing just enough vulnerability to seep out, his arrogance is delivered with such charm that it's nearly impossible not to like him, and he is, for my money, a very funny actor."

Meanwhile, Lipsey explained that Kate is the "straight guy" to Jack.

"So we cast a consummate comedic performer, Lucy Punch," he said. "It was a gamble that pays off, for she both found comedy where we hadn't seen it and humanity where it was crucial for gaining empathy. She sets Jack up beautifully, paving the way for full comic payoff."

He added: "As for chemistry, well I can only hope the rest of you will feel as I do. You can't cast for chemistry, I don't think. You can take an educated guess but I think most shows that have it just got lucky... Time will tell, but I think these two have it."

Vexed continues on Sunday at 9pm on BBC Two.